Robust Tolerance Research Articles

Tolerogenic Nanoparticles Impacting B and T Lymphocyte Responses Delay Autoimmune Arthritis in K/BxN Mice.

Current treatments for unwanted antibody responses largely rely on immunosuppressive drugs compromising overall immunity. New approaches to achieve antigen-specific tolerance are desirable to avoid unwanted side effects. Several nanoparticle-based approaches that utilize different mechanisms to tolerize the B or T cell arms of the humoral immune response have shown promise for induction of antigen-specific tolerance, raising the possibility that they could work synergistically if combined. Earlier we showed that Siglec-engaging tolerance-inducing antigenic liposomes (STALs) that display both an antigen (Ag) and glycan ligands of the inhibitory co-receptor CD22 (CD22L) lead to robust antigen-specific B cell tolerance to protein antigens in naive mice. In another approach, administration of free Ag with poly(lactic-co-glycolic acid)-rapamycin nanoparticles (PLGA-R) induced robust antigen-specific tolerance through production of regulatory T cells. Here we illustrate that coadministration of STALs together with PLGA-R to naive mice induced more robust tolerance to multiple antigen challenges than either nanoparticle alone. Moreover, in K/BxN mice that develop spontaneous autoimmune arthritis to the self-antigen glucose-6-phosphate-isomerase (GPI), co-delivery of GPI-LP-CD22L and PLGA-R delayed onset of disease and in some mice prevented the disease indefinitely. The results show synergy between B cell-tolerizing STALs and T cell-tolerizing PLGA-R and the potential to induce tolerance in early stage autoimmune disease.

Assessing the adaptability of urban tree species to climate change impacts: A case study in Shanghai

Urban forests and trees are affected by potential biotic and abiotic climate change impacts. To enhance urban forest adaptability and resilience to climate change impacts, tree species with high local climate adaptability and robust stress tolerance should be identified and selected. Climate events in the Shanghai area, such as late frost, chilling, heat waves, drought, typhoons, waterlogging, soil salinization, pests, and disease, directly or indirectly impact urban forests and trees. For urban tree species selection in the context of climate change, an assessment framework was proposed and applied to assess the climate change adaptability of 65 urban tree species in Shanghai using a method combined with quantitative data and qualitative descriptions. In this study, the climate types of tree species were divided into four groups according to annual mean temperature (AMT) and annual precipitation (AP): temperate, cool subtropical, warm subtropical, and moist subtropical species. The results showed that hardness, heat tolerance, chilling requirement, and drought tolerance were categorized as climate-related tolerances, while other tolerances were categorized as non-climate-related tolerances. The tree species’ optimal AMT and AP were significantly correlated with climate-related tolerances, but they did not respond to the non-climate-related tolerances. The warm subtropical species had higher stress tolerances than other climate types in the Shanghai area; therefore, the warm subtropical species with high tolerances were the most suitable alternatives for urban tree species selection with regards to Shanghai’s climate change impacts. This study also found that the AMT optimum is a better index to reflect tree species’ climate-related tolerances rather than the AP optimum. Finally, the adaptability assessment framework of climate change impact will offer guidance for future-oriented urban forest management and urban tree species selection in Shanghai.

Prediction Model for Coal Spontaneous Combustion Based on SA-SVM.

Accurate predictions of the coal temperature in coal spontaneous combustion (CSC) are important for ensuring coal mine safety. Gas coal (the Zhaolou coal mine in Shandong Province, China) was used in this paper. A large CSC experimental device was adopted to obtain its characteristic temperatures from the macroscopic characteristics of gas production. A simulated annealing-support vector machine (SA-SVM) prediction model was proposed to reflect the complex nonlinear mapping between characteristic gases and the coal temperature. The risk degree of CSC was estimated in the time domain, and the model was verified by using in situ data from an actual working face. Furthermore, back-propagation neural network (BPNN) and single SVM methods were adopted for comparison. The results showed that the BPNN could not adapt to the small-sample problem due to overfitting and the output of a single SVM was unstable due to its strong dependence on the setting of hyperparameters. Through the SA global optimization process, the optimal combination of hyperparameters was obtained. Therefore, SA-SVM had higher prediction accuracy, robustness, and error tolerance rate and better environmental adaptability. These findings have certain practical significances for eliminating the hidden danger of CSC in the gob and providing timely warnings about potential danger.

Constructing N, P-dually doped biochar materials from biomass wastes for high-performance bifunctional oxygen electrocatalysts

The large scale lignocellulosic biomass wastes could also be regarded as abundantly-available renewable resources, and how to convert them into value-added products via sustainable approaches is still a big challenge. In this work, we demonstrated a facile pyrolysis method to construct N, P-dually doped biochar materials from the lignocellulosic biomass wastes. The as-synthesized N, P-dually doped biochar samples could act as electrocatalysts for oxygen reduction and evolution reactions (ORR/OER), showing excellent catalytic performance and long-term durability, as well as robust tolerance to CO and methanol. The unique hierarchical porous structure, favorable electronic structure modified by the N and P doping, as well as a variety of defect sites induced by the N and P doping into the carbon framework were identified as the main contributions to the prominent catalytic activity of the as-synthesized N, P-dually doped biochar materials. We expect this work would spur more efforts into developing advanced materials from the large scale lignocellulosic biomass wastes.

Fault tolerant linear parameter varying flight control design, verification and validation

This article presents the design, verification, and validation of a fault tolerant linear parameter varying controller for JAXA’s MuPAL-α aircraft. The design focuses on the synthesis of a lateral/directional LPV controller robust to velocity changes and actuator uncertainty, and with the scheduling variable chosen to make it fault tolerant to aileron and/or rudder loss-of-efficiency faults. The verification activities include linear, frequency and time, analyses as well as time-domain simulations –the latter with the LPV controller as it will be implemented in the aircraft. The validation is performed in the so-called Aircraft-In-the-Loop, which is best described as a type of aircraft Iron-Bird test-bench where the full aircraft is connected in the hangar to an external computer that allows to introduce exogenous effects (such as wind/gust) while using pilot, or also computer user-defined, commands. The verification and validation results show very good robustness and fault tolerance characteristics of the LPV controller for a wide set of fault conditions and speeds. The article discusses in detail the design and implementation issues for such type of controllers.

Multi-UAV Distributed Collaborative Coverage for Target Search Using Heuristic Strategy

Collaborative coverage for target search using a group of unmanned aerial vehicles (UAVs) has received increasing attention in recent years. However, the design of distributed control strategy and coordination mechanisms remains a challenge. This paper presents a distributed and online heuristic strategy to solve the problem of multi-UAV collaborative coverage. As a basis, each UAV maintains a probability grid map in the form of a locally stored matrix, without shared memory. Then we design two evaluation functions and related technical strategies to enable UAVs to make state transfer or area transfer decisions in an online self-organizing way. The simulation results show that the algorithm integrates geometric features such as parallel search and internal spiral search, and is not interfered by factors such as sudden failure of UAVs, changes in detection range, and target movement. Compared with other commonly used methods for target search, our strategy has high search efficiency, good robustness, and fault tolerance.

Complete genome sequencing of Peyer\u2019s patches-derived Lactobacillus taiwanensis CLG01, a potential probiotic with antibacterial and immunomodulatory activity

BackgroundThe genus Lactobacillus is an important component of the gastrointestinal tract of human and animals and commonly considered as probiotic. L. taiwanensis has long been proposed to be a probiotic whereas understanding on this species is still in its infancy. Genomic information of L. taiwanensis is fairly limited. Extensive characterization of its beneficial traits is needed.ResultsA new strain CLG01 of L. taiwanensis was isolated from mouse Peyer’s patches. We established its probiotic profile through in vitro experiments. Complete genome of this strain was also sequenced and analyzed. L. taiwanensis CLG01 showed robust tolerance to acid and a degree of tolerance to bile salt with a promising antibacterial activity against a broad spectrum of pathogenic bacteria. In vitro treatment of mouse RAW 264.7 macrophage cells with heat-killed bacteria and bacterial supernatant of L. taiwanensis CLG01 resulted in enhancement of immune responses and upregulated expression of TNF-α and IL-6. The strain CLG01 also increased the IL-10 production of macrophages when co-treated with lipopolysaccharide (LPS). Complete genome of L. taiwanensis CLG01 contained a 1.89 Mb chromosome and two plasmids. Further genomic analysis revealed the presence of genes related to its resistance to different stresses and the beneficial effects mentioned above. Moreover, biosynthetic gene clusters (BGCs) encoding antimicrobial peptides, like bacteriocin, linear azol(in)e-containing peptide (LAP) and lanthipeptide, were also identified in the genome of L. taiwanensis CLG01.ConclusionsL. taiwanensis CLG01, isolated from mouse Peyer’s patches, is the first L. taiwanensis strain with both phenotypes and genotypes systematically studied. These preliminary data confirmed the role of L. taiwanensis CLG01 as a potential probiotic candidate with antibacterial and immunomodulatory activity, which provide insight for further investigation to this species.

The human visual system and CNNs can both support robust online translation tolerance following extreme displacements.

Visual translation tolerance refers to our capacity to recognize objects over a wide range of different retinal locations. Although translation is perhaps the simplest spatial transform that the visual system needs to cope with, the extent to which the human visual system can identify objects at previously unseen locations is unclear, with some studies reporting near complete invariance over 10 degrees and other reporting zero invariance at 4 degrees of visual angle. Similarly, there is confusion regarding the extent of translation tolerance in computational models of vision, as well as the degree of match between human and model performance. Here, we report a series of eye-tracking studies (total N = 70) demonstrating that novel objects trained at one retinal location can be recognized at high accuracy rates following translations up to 18 degrees. We also show that standard deep convolutional neural networks (DCNNs) support our findings when pretrained to classify another set of stimuli across a range of locations, or when a global average pooling (GAP) layer is added to produce larger receptive fields. Our findings provide a strong constraint for theories of human vision and help explain inconsistent findings previously reported with convolutional neural networks (CNNs).

Nano/submicrometer-emulsion oily wastewater treatment inspired by plant transpiration

<h2>Summary</h2> Oily wastewater treatment has attracted considerable attention because the wastewater poses a serious threat to the safety of drinking water, the ecological environment, and human health. Although significant progress has been made with regard to the development of superwettable separation membranes, there is a need for addressing the challenges that arise with the treatment of nano/submicrometer-emulsion oily water, oily seawater, and acid-base-corrosion oily wastewater. Herein, inspired by plant transpiration, a solar-driven device is developed that is based on wood, poly(vinyl alcohol), and hydroxylated multiwalled carbon nanotubes; this device demonstrates a purification efficiency of up to 99.7% toward various nano/submicrometer-emulsion oily wastewaters. Remarkably, owing to the outstanding desalination capacity and robust acid-alkali tolerance, the prepared device achieved a one-step production of fresh water from oily seawater and acid-base-corrosion oily water. Therefore, the development of this device provides a method for treating oily wastewater to produce fresh water.

Research on Project Knowledge Management Risk Early Warning Based on Bp Neural Network

On the premise of analyzing various evaluation methods and means and constructs the comprehensive evaluation model of external knowledge transfers risk of transformation enterprises. BP network has robustness and fault tolerance, it is distributed storage of information, local damage will be a certain degree of reduce the network performance, does not result in a catastrophic risk, tolerance with a larger error in the input value, and even individual errors exist, at the same time each activity unit has the independence of the information processing, which can realize the parallel computing, improve speed.

Controlled induction of immune tolerance by mesenchymal stem cells transferred by maternal microchimerism

Feto-maternal immune tolerance is established during pregnancy; however, its mechanism and maintenance remain underexplored. Here, we investigated whether mesenchymal stem/stromal cells (MSCs) as non-inherited maternal antigens (NIMAs) transferred by maternal microchimerism could induce immune tolerance. We showed that MSCs had a potential equivalent to hematopoietic stem and progenitor cells (HSPCs) to induce immune tolerance and that MSCs were essential to induce tolerance to MSC-specific antigens. Furthermore, we demonstrated that MSCs as NIMAs transferred by maternal microchimerism could induce robust immune tolerance that can be further enhanced using a drug. Our data shed light on induction of immune tolerance and serve as a foundation to develop new therapies using maternally derived cells for autoimmune or genetic diseases.

Platelet gene therapy induces robust immune tolerance even in a primed model via peripheral clonal deletion of antigen-specific T cells

While platelet-specific gene therapy is effective in inducing immune tolerance to a targeted protein, how the reactivity of pre-existing immunity affects the efficacy, and whether CD8 T cells were involved in tolerization, is unclear. In this study, ovalbumin (OVA) was used as a surrogate protein. Platelet-OVA expression was introduced by 2bOVA lentivirus transduction of Sca-1+ cells from either wild-type (WT)/CD45.2 or OT-II/CD45.2 donors followed by transplantation into OVA-primed WT/CD45.1 recipients preconditioned with 6.6 Gy of irradiation. Sustained platelet-OVA expression was achieved in >85% of OVA-primed recipients but abolished in animals with high-reactive pre-existing immunity. As confirmed by OVA rechallenge and skin graft transplantation, immune tolerance was achieved in 2bOVA-transduced recipients. We found that there is a negative correlation between platelet-OVA expression and the percentage of OVA-specific CD4 T cells and a positive correlation with the OVA-specific regulatory T (Treg) cells. Using the OT-I/WT model, we showed that antigen-specific CD8 T cells were partially deleted in recipients after platelet-targeted gene transfer. Taken together, our studies demonstrate that robust antigen-specific immune tolerance can be achieved through platelet-specific gene therapy via peripheral clonal deletion of antigen-specific CD4 and CD8 T effector cells and induction of antigen-specific Treg cells. There is an antagonistic dynamic process between immune responses and immune tolerance after platelet-targeted gene therapy.

Modulation-transparent and Robust Frequency Offset and Phase Tracking Scheme Using Self-learning Kalman Filter for Intelligent Receiver

A joint and robust frequency offset (FO) and phase noise tracking scheme using self-learning Kalman filter is proposed and demonstrated experimentally. In our scheme, a self-learning Kalman filter based on kurtosis error is used to track FO and phase noise simultaneously in a constellation decision-free manner. Then, a mean-shift clustering-assisted maximum likelihood estimator is used for residual phase noise compensation. Simulation results indicate that the proposed scheme has advantages in FO estimation accuracy, OSNR sensitivity penalty, and FO jitter rate tolerance and nonlinearity tolerance, compared with the conventional FO and phase noise estimation scheme. With 7% FEC threshold, the proposed scheme can tolerate FO jitter rate up to 10 MHz for 16QAM, which is around 100 times and 20 times than that of VVPE1 +BPS and FFT+UCPE. With 1 dB OSNR penalty, the linewidth tolerance of the proposed scheme is 300 kHz for 64QAM, which is around 30 times and 5 times than that of FFT+UCPE+ML and FFT+ VVPE2. For 16QAM, the proposed scheme also shows excellent nonlinearity tolerance over wide launched power, and it provides around 0.4 dB and 0.2 dB Q-factor improvement over VVPE1+ VVPE2 VVPE1 +BPS for 16QAM, respectively. The 28GBaud PDM 16QAM experimental results also indicate that the proposed scheme outperforms the rest of the tested scheme under both back-to-back and fiber transmission cases. With optimal launched power, the proposed scheme can provide around 0.2 dB, 0.4 dB, and 0.7 dB Q-factor improvement over VVPE1 +BPS, FFT+UCPE, and VVPE1+ VVPE2 after 915 km fiber transmission, respectively. To the best of our knowledge, it is the first time that a joint and modulation transparent with robust nonlinearity and FO jitter rate tolerance is proposed and demonstrated for 64QAM.

Visible-light induced metal-free cascade Wittig/hydroalkylation reactions

Through a relay olefination and radical addition process, we developed cascade Wittig/hydroalkylation reactions induced by visible light. This metal-free radical approach features mild conditions, robustness, and excellent functionality tolerance.

Design of Modern Distributed Systems based on Microservices Architecture

Distributed systems are very commonplace nowadays. They have seen an enormous growth in use during the past few years. The idea to design systems that are robust, scalable, reliable, secure and fault tolerance are some of the many reasons of this development and growth. Distributed systems provide a shift from traditional ways of building systems where the whole system is concentrated in a single and indivisible unit. The latest architectural changes are progressing toward what is known as microservices. The monolithic systems, which can be considered as ancestors of microservices, cannot fulfill the requirements of today’s big and complex applications. In this paper we decompose a monolithic application into microservices using three different architectural patterns and draw comparisons between the two architectural styles using detailed metrics that are generated from the Apache JMeter tool. The application is created via .NET framework, uses the MVC pattern and is fictive. The two comparable apps before testing with Apache JMeter, will be deployed in almost identical hosting environment in order to gain results that are valuable. Using the generated data, we deduce the advantages and disadvantages of the two architectural styles.

A Stochastic Logic-Based Fuzzy Logic Controller: First Experimental Results of a Novel Architecture

In stochastic computing (SC) systems numbers are represented with mean values of random binary sequences. This paper introduces a novel fuzzy inference architecture, in which the computational mechanism is based on stochastic logic (SL). First, the basic concept of SL is described, then the architecture of the SL-based fuzzy logic controller (SFLC) is built up systematically using the derived stochastic elements. The second part of the paper demonstrates the application of the proposed techniques, where the SFLC-based control performance is evaluated on a real mechatronic system. The results show that the SL-based approach provides effective and robust control performance, simple architecture and high noise tolerance. The proposed method is also benchmarked against conventional FLCs indicating that the robustness of the stochastic architecture allowed to outperform the benchmark controllers in noisy environments.

Applying Differential Wave-Front Sensing and Differential Power Sensing for Simultaneous Precise and Wide-Range Test-Mass Rotation Measurements

We propose to combine differential wave-front sensing (DWS) and differential power sensing (DPS) in a Mach-Zehnder type interferometer for measuring the rotational dynamics of a test-mass. Using the DWS method, a high sensitive measurement of 6 nrad Hz−1/2 in sub-Hz frequencies can be provided around the test-mass nominal position ( mrad), whereas the measurement of a wide rotation range ( mrad) is realized by the DPS method. The interferometer can be combined with deep frequency modulation (DFM) interferometry for measurement of the test-mass translational dynamics. The setup and the resulting interferometric signals are verified by simulations. An optimization algorithm is applied to find suitable positions of the lenses and the waist size of the input laser in order to determine the best trade of between the slope of DWS, dynamic range of DPS, and the interferometric contrast. Our simulation further allows to investigate the layout for robustness and design tolerances. We compare our device with a recent experimental realization of a DFM interferometer and find that a practical implementation of the interferometer proposed here has the potential to provide translational and rotational test-mass tracking with state-of-the-art sensitivity. The simple and compact design, and especially the capability of sensing the test-mass rotation in a wide range and simultaneously providing a high-precision measurement close to the test-mass nominal position makes the design especially suitable for example for employment in torsion pendulum setups.

Chemoselective Amide-Forming Ligation Between Acylsilanes and Hydroxylamines Under Aqueous Conditions.

We report the facile amide-forming ligation of acylsilanes with hydroxylamines (ASHA ligation) under aqueous conditions. The ligation is fast, chemoselective, mild, high-yielding and displays excellent functional-group tolerance. Late-stage modifications of an array of marketed drugs, peptides, natural products, and biologically active compounds showcase the robustness and functional-group tolerance of the reaction. The key to the success of the reaction could be the possible formation of the strong Si-O bond via a Brook-type rearrangement. Given its simplicity and efficiency, this ligation has the potential to unfold new applications in the areas of medicinal chemistry and chemical biology.

Modular multilevel converter based multi-terminal hybrid AC/DC microgrid with improved energy control method

With the large-scale integration of the distribution generations (DGs) and the increasing medium-voltage and low-voltage DC power demands, multi-terminal hybrid AC/DC microgrid has drawn great attention from researchers around the world. In order to reduce the number of power conversion stages and meet DC transmission demands under different DC voltage levels, this paper proposes a four-terminal interconnection scheme of the hybrid AC/DC microgrid, connecting one medium-voltage AC (MVAC) terminal, one medium-voltage DC (MVDC) terminal and two low-voltage DC (LVDC) terminals. The proposed interconnection scheme includes a modular multilevel converter (MMC) as the main interlinking converter of the MVAC grid and MVDC microgrid, and a series of dual active bridges (DAB) converters as two isolated LV DC microgrid interfaces. It has more flexibility for power supplies, especially MVDC transmission, and a more robust tolerance for unequal power distribution between the two LVDC Microgrids. To realize the DC capacitor voltage balancing control, an improved energy control method is proposed in this paper. The proposed method keeps DC capacitor voltage balance and AC current zero on the MVDC transmission lines, which contributes to the stability of the MVDC microgrid. In addition, the symmetry of the AC currents is also guaranteed with this control method. Validation results of a four-terminal hybrid AC/DC microgrid verify the effectiveness of the proposed microgrid and control scheme.

A Chernov bound for robust tolerance design and application

Within an industrial manufacturing process, tolerancing is a key player. The dimensions uncertainties management starts during the design phase, with an assessment on variability of parts not yet produced. For one assembly step, knowledge can be gained from the tolerance range required for the parts involved. In order to assess output uncertainty of this assembly in a reliable way, this paper presents an approach based on the deviation of the sum of uniform distributions. As traditional approaches based on Hoeffding inequalities do not give accurate results when the deviation considered is small, an improved upper bound is proposed. Then, the impact of the stack chain geometry on the bound definition is discussed. Finally, an application of the proposed approach in tolerance design of an aircraft sub-assembly is detailed. The main interest of the technique compared to existing methodologies is the management of the confidence level and the emphasis of the explicit role of the balance within the stack chain.